By this Author: TadHerman

What do some teachers do during the Summer?

It is in my nature to find a little something school-related to do in the summer months with an element of a new place to explore. Last year, the Great American Solar Eclipse served that purpose. It was more a “fun” thing to do to quench the thirst of my inner nerdy astronomer, but it all came back to school with me to share with the students. You are more than welcome to look through my blog from last summer’s adventure. Click on https://Solar Eclipse Trip

The main school-related thing I have done the past 14 summers is train teachers around the country to teach the PLTW Principles of Engineering course. However, during my research for last year’s eclipse trip, I discovered a National Science Foundation (NSF) granted Research Experience for Teachers program in Radio Astronomy...Click on DSPIRA

I was intrigued that I would have an opportunity to actually DO some science rather than just TEACH the science, but still have the chance to pass my experience onto the students. Applied…Accepted…Now, here in West Virginia!

Morgantown

West Virginia University has 2 main campuses and a very unique way to get from one campus to the other. You get in these little cars and it will take you on an elevated rail system from place to place. Unfortunately, it is closed for repair and upkeep in the summer.

Personal Rapid Transit - PRT

Morgantown is a hilly little place. So, it is very easy to come across some nice views from many places. The Evansdale Campus is on a hilltop about 300 feet about the river.

Nice Lounge for Lunch

DSPIRA

Digital Signal Processing In Radio Astronomy

The easy part- RADIO ASTRONOMY

This is the branch of astronomy that explores the radio end of the Electro-Magnetic Spectrum (EMS). We “SEE” the Sun, Moon, stars and planets in the sky with our eyes, and with the assistance of telescopes, because our eyes are sensitive to the VISIBLE LIGHT portion of the EMS. We are familiar with the other parts of the EMS such as X-rays, Ultra-Violet, Microwaves, RADIO, but we don’t SEE them directly. Things in space generate Electro-Magnetic Radiation right across the full EMS. We need special detectors to see them.

Electro Magnetic Spectrum

SIGNALS

"Signal" has become a very common word in everyone’s everyday vocabulary. Thing about the last time you used that word. It was probably something like, “Dad, why are we on vacation in the mountains? I can’t get any signal for my phone”, or “My signal strength in 4 bars.” Simply put, SIGNAL, in this context, IS Electro-Magnetic INFORMATION. Nearly the whole of human knowledge and information is available through your cell phone. The signals are “in the air”, or at least available to be generated at your whim. If you ask SIRI, “What time is the sunrise today in Sunrise, Florida?” Your phone will generate a RADIO SIGNAL that travels at the speed of light to a receiver. The information you requested will be retrieved from a computer somewhere and turned into a RADIO SIGNAL that will be transmitted back to you…all in a matter of seconds. Now, if you go out on a clear night and see the Full Moon, you might not consider that a SIGNAL, but it is. Light from the Sun is reflecting off the Moon and travelling to you where you get enough information for your brain to PROCESS (coming up) the Signal enough to recognize it as the Moon.

SIGNAL PROCESSING
The signals are everywhere… It is currently a beautiful day outside. The Sun is out, the sky is blue, there may be some clouds out there…or so I think, because I am sitting inside with the shades pulled typing this up now. If I step outside and use my eyes to receive the signals, and let my brain PROCESS the SIGNALS, then I will know for sure…I am going to take a quick break and go outside to process some signals…

…Yep, I was right! Oh, and I used the digital camera to capture and do some DIGITAL SIGNAL PROCESSING so I could share with you what I saw.

The science of astronomy is all about signal processing. We sit here on Earth with a very limited capacity to travel to all these exotic objects we see. Astronomers have to use telescopes to SEE the universe around us. The telescopes mainly look at selected objects and record huge quantities of data in computers for the scientists, or their computer software, to sort through the data to help us discover the Universe. An example of the huge quantity of data gathered in astronomy...The New Horizons space craft passed by Pluto in July 2015. It spent a few precious hours in close proximity to the (dwarf) planet where all the instruments were busy receiving signals. It took the spacecraft until Oct 2016 for all the data to be transmitted back to Earth. The Data Processing will go on for years to come.

Pluto Data Dump

DIGITAL SIGNAL PROCESSING

The DIGITAL part is simply that we use computers to aid us in processing the data. Here is an example of using a digital picture I took, and using a photo editing program to PROCESS more information from the original SIGNAL.

Show Up at Room G23 in Engineering Building 9 am Monday

There is always that first hour of "Welcome", "Introduce yourself", "This is what to expect in the coming weeks"

There are 3 College Professors, 1 graduate, and 2 undergraduates involved in running the program. There are 6 high school teachers participating in the training. We are from West Virginia (2), North Carolina, Rhode Island, Florida, and New York. We teach physics, astronomy, space and earth sciences, engineering, and biology. Two of the participants are returning from last year (I guess they liked it that much.)

Kevin Bandura- The main organizer of the program - known as Special K

First Day - First Hour

Day 1 was mainly introductory. We toured the building and the classrooms we would be using. We went to the roof to see one of the horn scopes in action...a preview of what we will be building.

Horn Scope from Last Year...Will ours be like this

After Lunch, we received a nice gift. A 2-in-1 laptop to run our equipment...and to take home with us!. Then, our grad student, Pranav, started teaching us how to use the radio equipment.

Day One Gift

An Expensive Radio

Our daily routine for a majority of our 4 weeks at WVU will be 2 lecture classes in the morning and lab in the afternoon.

DIGITAL SIGNAL PROCESSING

This class is taught by Dr. Natalia Schmid. It is meant to be an overview of the math behind the processing, and the purpose that this in the main method of making sense of the data coming in from space.

Natalia Schmid

We get to dabble with Fourier Series and Transforms....Sine and Cosine Functions...Real and imaginary numbers...Oh Boy. The stuff we are encountering in this class is stuff that a 3rd year Electrical Engineering student would dive into fully.

fourier series in 3d

There are 2 main things in the Electro-Magnetic Radiation we receive. The stuff we want (signal), and the stuff we don't (noise). In this picture I took, I wanted to emphasize that I could see the NYC skyline from Mt Beacon. Even though it was a relatively clear day, I had to deal with 50+ miles of hazy air between me and NYC. With the photo editing software, I managed to pull out the details with much more contrast.

ASTRONOMY

This class is taught by Dr. Loren Anderson. Since we will ultimately be looking for neutral Hydrogen in plane of the Milky Way Galaxy with our horn telescopes, he will be dissecting a first year general astronomy course to incorporate the coordinates of the celestial sky and where to look from our location on Earth...details about the Milky Way Galaxy and the nature of Hydrogen gas.

Loren Anderson

Skies and Spheres

On Friday, we were able to go to WVU's planetarium to explore the coordinate systems in 3D.

WVU Planetarium

New Age Planetarium Projector

WVU 14 inch Telescope

We had to go to the main campus for the planetarium, so we had to find some lunch before returning.

Going to High Street for Lunch

LAB-GNURADIO-SOFTWARE DEFINED RADIO
After lunch, our efforts will be hands-on work to program our computers to process the data we receive from our horn telescopes (which will be built in Week 2). We have the leadership of mighty EE grad student, Pranav!

Pranav

Here are a few shots of some of the fine things we have worked on so far. As I type this, I am listening to a local radio station on my new laptop (you saw the picture earlier).

Sources, filters, amplifiers, demodulators, Fast Fourier Transforms....lots to learn here in the coming weeks.

Screen Shot of Radio Station Strengths

GnuRadio Programming

Resulting Wave Pattern from Program

What is a Horn Telescope?

Part of Kevin' Bandura's goal for this program is to develop a low cost radio telescope (<$100) that could be easily constructed by, and for, high school teachers to use with their students. One of the strongest sources of radio waves coming from space is the radiation of 21-cm wavelength radio waves generated by cold neutral hydrogen from the plane of our Milky Way Galaxy.

Neutral Hydrogen Map of Milky Way Galaxy

The following image is a screen capture from the Wikipedia article on Hydrogen Lines. It seems to contain the basic information about what the 21-cm Hydrogen line can tell us about our own galaxy...

The Horn

An optical telescope is curved such to reflect the visible light into a sharp image that can be seen. The Horn is quite different in that it is designed to reflect the radio waves into the resonance can chamber. The antenna is placed at an anti-node point of the standing wave we wish to look at (the 21-cm), thus (21 cm) / 4 = 5.5 cm. Here is a quick diagram to explain the nature of the Horn.

There won't be a sharp image, but there will be a stronger signal in the general direction it is pointing.

Our Week Two--No Lecture Classes (just stating the facts)

The main 2 goals were for us to make a horn telescope for each of us (6), and to have the lovely experience of soldering the 40 or so tiny components of the Low Noise Amplifier on the circuit board. Since we had the 4th of July off (Wed), we worked 4 days at creating the 6 scopes. With John and Howard here last year, and Dan seeing lots of possible improvements, there was a fair amount of brainstorming ways to make it more portable. Eventually, we got into an assembly line mentality and people fell into niches that needed to be filled to get the job done. We spent the time in a nice tech lab that would make my fellow tech teachers drool.

The two major improvements over last year's design was:

1) To make notched 2x4 base pieces instead of bolting them together. This allowed for quick assembly and disassembly.

2) To make a "horn holder". Basically a cage slightly bigger than the can for the can/hold assembly to slide in. Pieces of styrofoam are used to wedge it tightly in place. Last year's design had it taped in place. Again, quicker assembly and disassembly.

An aluminum screen horn design is being worked on to allow wind to blow through horn walls to reduce shaking or tipping...Stay tuned! (That's a radio astronomer's joke.)

Getting ready to build scopes in the Shop

Getting Jinky with it

Lots of Conducting Aluminum Tape

How Much Wood...

Trying a new notch design

Cutting some wood

Let's Make Some Horns

How many science teachers does it take to cut a metal can

Find Your Inner Balance

Putting the A in STEAM

Take us to your Leader

And the rent is only $400 a month!

Horn Head from ...Florida

Designer Horn Wear...Wait a minute...Where's my other foot?!

Friday afternoon...time for the weekend...all parts ready, but no fully assembled scopes. Wait for Monday!

Soldiering on through Soldering

I will bring back the simple diagram of the horn to talk about an omission. When the radio waves set up in the resonant chamber of the can, the signal will be picked up by the 5.5 cm copper antenna. That very low intensity wave then goes to the computer. At the back end of the can is a LOW NOISE AMPLIFIER (LNA)

Horn Diagram wLNA

This is a specifically designed circuit (designed by Special K) for the purpose of this horn scope, so we couldn't rely on Walmart or Amazon to have them ready for us...We had to make them solder by solder.

On Thursday, they took two of us to the slaughter house...I mean solder house (there was a point where we felt we would never return alive, so the mistake is honest) to put the 40 or so inductors, capacitors, resistors, relays onto the pre-printed circuit board.

Now, I have soldered copper pipes for plumbing (big stuff...I can see), but I never have soldered micro components to a circuit board. So, Something New. For us newbies, this was to be a full day event. Alexis and I went on Thursday, Dan and New John on Friday. Old John and Howard did it last year and will go do another one on Monday when we are back in class.

Without going into much detail, this had a significant element of frustration involved with it. Trying to pick up a one millimeter long resistor with tweezers in one hand while heating a 1/4 millimeter dab of solder onto the appropriate square on the circuit board with the other. Then, place the resistor in the molten dab of solder so it cools and hardens in place, and repeating this about 80 times...YIKES! It is definitely a skill to be developed over time. I found the limit to my ability to see small and close, and I have to thank Alexis and her younger eyes for much assistance. Enjoy the micro show below...

Soldering 101...All in. That inductor is one of the big components!

Thank you Macro Lens

Holy Crap, that's small

Who wrote those numbers on there

All done...I hope they work